High Intensity Focused Ultrasound (HIFU) offers a non-invasive, non-surgical, bloodless, outpatient treatment for uterine fibroid tumors. These tumors develop in over half of all women, and account for approximately 30 percent of all hysterectomies. This proposal will develop an integrated transvaginal HIFU probe and imaging transducer for fibroid treatment. The proximal transvaginal approach facilitates optimal HIFU control, improves aiming and minimizes complications. Phase I of this grant successfully constructed a lab prototype HIFU/Imaging unit, measured the speed and attenuation of sound in excised human fibroids, and established optimal treatment parameters (frequency, intensity and dose). Phase II will utilize several imaging modalities to map numerous in-situ fibroid tumors and evaluate the range of uterine and intervening tissue structures in women, develop an anatomically correct integrated HIFU/Imaging clinical prototype probe, evaluate the safety and efficacy of this treatment in sheep studies and evaluate this probe?s placement and imaging characteristics in humans. This grant will develop the properly shaped HIFU probe and investigate the safety and efficacy of HIFU to treat fibroids in Phase Ill human clinical studies. Dramatic improvements in patient treatment, reduced complication rate, reduction in health care costs, reduced recovery time and preservation of a women?s fertility are the potential results. PROPOSED COMMERCIAL APPLICATION: The goal of this research is to develop a non-surgical, outpatient treatment system for uterine fibroid tumors based upon high intensity focused ultrasound (HIFU). It is anticipated that this treatment will improve patient care, facilitate an alternative to hysterectomy, and result in significantly lower treatment cost. Ultimately, this treatment approach may also provide an option to preserve fertility and improve reproductive outcomes in patients with fibroid tumors.